How to add elements to an array in Matlab

In this extensive article, we will explore how to add elements to a MATLAB array. We’ll explain the concept behind arrays and discuss how they are represented within the MATLAB environment. Additional …

Updated October 6, 2023

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In this extensive article, we will explore how to add elements to a MATLAB array. We’ll explain the concept behind arrays and discuss how they are represented within the MATLAB environment. Additionally, you will discover various techniques for appending or inserting elements into an existing array while maintaining its data structure. We will provide code samples throughout this tutorial to better illustrate each method’s usage. By reading this guide, you can learn more about effectively managing arrays in MATLAB and efficiently solving real-world problems that involve manipulating various types of arrays.


Arrays are one of the fundamental data structures in MATLAB that help store multiple elements of a particular type (numeric, character, logical) in a single variable. They provide an organized way to handle large amounts of data and support many operations such as sorting, indexing, and element access. In this article, we will focus on understanding the process of adding elements to MATLAB arrays using different methods like concatenation, appending, inserting, and reshaping.

1. Concatenate Arrays

Concatenating two arrays is the most straightforward way to merge multiple arrays into one. This can be achieved by simply using the square brackets ([]) with the appropriate comma-separated list of array elements. For instance, if you have two numeric arrays A and B, you may concatenate them as follows:

A = [1 2 3; 4 5] B = [6 7; 8 9] C = [A; B]

In the above example, we combined Arrays A and B by using a semicolon to separate each array and create a new Array C consisting of all the elements from both arrays. The output for this code would be:

C = 1 2 3 4 5 6 7 8 9

2. Append Elements to an Array

The append function allows you to add one or more elements to the end of a given array while maintaining its original data type and dimensions. It can be used on both numeric and non-numeric arrays. You may use it in conjunction with the comma operator to concatenate multiple arrays:

A = [1 2] B = append(A, 3) % Append an element at the end of A B = [1 2 3] C = append([A B], 4) % Concatenate two arrays and then append another element C = [1 2 3; 1 2 3]

In this case, we first added a new value (3) to the end of Array A using append. We also concatenated Arrays A and B and finally appended another element (4) at the end of the resulting array C.

3. Insert Elements into an Array

The insert function allows you to add elements to a specific position within an existing array. This method is helpful when working with arrays where you need to insert new values at specific indices without changing the overall size of the array. For example, let’s say we have an array A = [1 2] and want to place the element 3 before the first element:

A = [1 2] B = insert(A, 0, 3) % Add element 3 at index 0 B = [3 1 2]

4. Reshape an Array

The reshape function is useful when you need to modify the shape or dimension of an array without changing its contents. For instance, if you have a two-dimensional numeric array A containing all even numbers, you can create a one-dimensional array B by reshaping:

A = [2 4; 6 8] % Two even numbers as a 2x2 array
B = reshape(A, [], 1) % Reshape to a row vector of even numbers
B =

In this example, we initially formed Array A with the first two even numbers, and then reshaped it into a one-dimensional Array B containing all even numbers in sequence.


Matlab offers multiple ways to manipulate arrays by adding or inserting elements, appending them to existing arrays, or changing their shape. In this article, we have explored the basic techniques you can utilize for working with MATLAB arrays: concatenation, appending new values using append, inserting elements at specific positions via insert, and reshaping an array’s dimensions using reshape. By understanding and applying these methods, you will be better equipped to handle diverse data sets in various domains while tackling real-world problems involving arrays in MATLAB.